NE58633BS,157 NXP Semiconductors, NE58633BS,157 Datasheet - Page 19

• Manufacturer Part Number: NE58633BS,157
• Description: IC AMP AUDIO .04W STER D 32HVQFN
• Manufacturer: NXP Semiconductors
• Type: Class Dr

Specifications of NE58633BS,157

• Output Type: Headphones, 2-Channel (Stereo)
• Package / Case: 32-VQFN Exposed Pad, 32-HVQFN, 32-SQFN, 32-DHVQFN
• Max Output Power X Channels @ Load: 40mW x 2 @ 16 Ohm
• Voltage - Supply: 0.9 V ~ 1.7 V
• Features: Depop, Differential Inputs, Microphone, Mute, Short-Circuit Protection
• Mounting Type: Surface Mount
• Product: Class-D
• Output Power: 40 mW
• Available Set Gain: 100 dB
• Thd Plus Noise: 1 %
• Supply Current: 5 mA
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• Audio Load Resistance: 32 Ohms
• Input Offset Voltage: 1 mV
• Input Signal Type: Single
• Minimum Operating Temperature: 0 C
• Output Signal Type: Differential, Single
• Supply Type: Single
• Supply Voltage (max): 1.7 V
• Supply Voltage (min): 0.9 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 935283227157; NE58633BS; NE58633BS

NXP Semiconductors
NE58633_3
Product data sheet
10.8.3.1 Conceptual diagram of feedback application
10.8.3 Feedback circuit
Figure 18
cancelling microphone samples the noise and music inside the acoustical plant.
The feedback solution employs a low cost, battery operated analog Active Noise
Reduction (ANR) technique. The topology uses negative feedback circuitry in which the
noise reduction microphone is placed close to the ear and headphone loudspeaker. By
detecting the noise with the microphone in the position closer to the ear, a noise
cancelling effect with high accuracy is realized. This technique produces a noise
cancelling signal that always minimizes the noise in the ear canal or entrance to the ear
canal. The audio signal is analyzed with exact timing with the noise cancelling signal. The
noise cancelling signal increases with increasing noise level.
The headphone loudspeaker or transducer is used to send the normal audio signal as well
as the feedback signal providing noise cancellation. The microphone is placed near the
loudspeaker and its output is amplified, filtered, and phase inverted by the feedback
network and sent back to the loudspeaker.
The design of the feedback filter for a given headphone plant involves a trade-off between
performance on one hand and stability and robustness with respect to variations of the
headphone plant on the other. Traditional feedback design methods use filter elements
such as, lead, lag and notch filters which are appropriately tuned to shape the audio
response of the system to obtain good performance with sufficient stability margins.
Fig 18. Feedback conceptual diagram
shows the typical feedback application diagram in the which the noise
human head
Rev. 03 — 19 January 2010
ear
Noise reduction class-D headphone driver amplifier
E
acoustic
compartment
or plant
external noise
transducer
(speaker)
noise detection
microphone
headphone
shell or body
2
H.P. driver
FILTER
AMP
electronic
compartment
NE58633
002aad928
NE58633
© NXP B.V. 2010. All rights reserved.
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